Slider for fastener strips



Dec. 31', 1963 JACOBS 3,115,689

SLIDER FOR FASTENER STRIPS Filed Jan. 19, 1961 [NV EN TOR. 37 is Phi/()0 E Jacobs A TTORNE YS United States Patent 3,115,689 LlD11R FGR FASTENER STRlPS Philip E. Jacobs, Glen Head, N.Y., assignor to Flexigrip, Inc, New York, N.Y., a corporation of New York Filed Jan. 19, 1961, Ser. No. 83,712 2 Claims. (Cl. 24--21) The present invention relates to improvements in a flexible slide fastener such as used to close an opening in a pouch or envelope and particularly to an improved slider for joining and for separating a pair of flexible closure strips having confronting interlocking elements.

The invention contemplates providing a pair of flexible closure strips formed of plastic or like suitable material each having a web portion and a marginal portion with the marginal portions at the edge of the web portions having confronting locking surfaces provided with interlocking channel and ridge elements which extend therealong. A slider straddles the edges of the strips and has opposed tapering sides tapering inwardly from a feed end toward a closing end for engaging and forcing the strips together when moved in a closing direction and has a separating finger for separating and releasing the strips when moved in an opening direction.

A feature of the invention is the provision of inwardly extending indentations on each of the sides at the closing ends thereof forming locking ridges assuring locking of the fastener strips. Another feature is the grooving of the slider finger to strengthen the finger and strengthen its connection to its associated parts.

Accordingly an object of the present invention is to provide a slide fasten-er with an improved slider having unique features improving the strength of the slider and improving its function both for closing and opening slider strips.

Another object of the invention is to provide a slider for a flexible slide fastener having an improved structure for closing the fastener insuring closure and permitting wider manufacturing tolerances.

Another object of the invention is to provide a slider of the above described nature having an improved structure for strengthening the separator finger of the slider which separates the fastener strips.

Other objects and advantages will become more apparent with the teaching of the principles of the invention in connection with the disclosure of the preferred embodiment thereof in the specification, claims and drawings, in which:

FIGURE 1 is a perspective View of a flexible slide fastener, showing fastener strips in section, constructed in accordance with the principles of the present invention;

FIGURE 2 is a vertical sectional view taken substantially along line IIII of FIGURE 1;

FIGURE 3 is an end elevational view of the slider taken from the feed end thereof;

FIGURE 4 is a bottom plan view of the slider; and

FIGURE 5 is an enlarged sectional view taken substantially along line VV of FIGURE 3.

As shown on the drawings:

A fastener of the type which the improved slider is particularly well adapted for use is illustrated in FIG- URES 1 and 2. The fastener incorporates first and second flexible closure strips 12 and 13 which can be secured to the edges of an envelope or a pouch or similar structure requiring a closure, such as by sealing or cementing. Slidably mounted on the closure strips and straddling the strips is a slider 14 which is moved in an opening direction (to the right as shown in FIGURE 1) to separate the closure strips 12 and 13 or in a closing direction (to the left in FIGURE 1) to join the closure strips 12 and 13.

The closure strip 12 includes a web portion 15 and a 3,115,639 Patented Dec. 31, 1963 2 marginal portion 16 extending substantially parallel and providing an extension of the web port-ion.

The closure strip 13 has a web portion 17 and a marginal portion 18. The marginal portion 18 is shown as turned inwardly or doubled back so as to lie alongside the web portion. An inner fold or crease 21 is formed at the juncture of the marginal portion 18 and the web portion 17 and this crease 21 may be formed with grooved sides so as to prevent the formation of a sharp juncture of material which could tear and would weaken the strip 13 and as shown on the drawings the portion of material above the crease 21 forms a hinge portion integrally joining the marginal portion 18 and the web portion 17. The marginal portion 16 is offset inwardly toward the other strip to provide a downwardly facing shoulder.

The closure strips 12 and 13 are employed in various closure environments such as by being attached to the edges of walls of an envelope, not shown. The envelope is opened or closed by moving the slider 14.

While the closure strips 12 and .13 are illustrated as a preferred form of closure with which the slider 14 is used, it will be understood that the features of the slider may be adapted to closure strips of other constructions, as will be appreciated by those skilled in the art.

The marginal portions 16 and 18 of the closure strips are provided with confronting interlocking means for joining the strips. The interlocking means are shown in the form of mating ridge and groove or channel elements. The closure strip 12 is shown as provided with ridges 22 having enlarged heads so as to define channels 23 therebetween. The channels lockingly receive ridges 24 on the closure strip 13. The ridges 24 have enlarged heads so :as todefine channels 25 therebetween which lockingly receive the ridges 22 of the first closure strip 12. In the arrangement illustrated, each of the ridges has an overhanging portion at one side so as to form a locking surface which engages with a locking surface of the overhanging portion on the ridge of the other closure strip, with the confronting locking surfaces shown in engagement at 26'.

In the preferred arrangement, each of the closure strips is provided with two channels and two ridges although different numbers may be employed and the ridges and channels preferably extend substantially parallel to the closure strips. As will be appreciated by those skilled in the art, other interlocking arrangements may be utilized in certain circumstances and in the preferred general arrangement the interlocking means on the confronting faces of the closure strips automatically interlock in response to the application of a lateral pressure forcing them together. The closure strips automatically separate by a separating force applied between the confronting surfaces so as to draw them apart. The application of the pressures or forces for inter-locking the strips or separating them is the function of the slider 14.

The strips are conveniently manufactured of plastic which is suitable for extruding and is flexible. Suitable materials for manufacturing the closure strips 12 and 13 include the thermoplastic and thermo-setting organic synthetic resins. Of particular importance for this use are the vinyl type resins such as polyvinyl chloride, polyvinyl acetate, polyvinyl chloride-polyvinyl acetate copolymers, and similar vinyl resins, and polyethylene. Rubber, either natural or synthetic is not a preferred material since, in the case of rubber, it is more difficult to control the degree of rigidity for interlocking engagement between the strips. However, by proper compounding and vulcanizing the rubber, the degree of rigidity can be con-trolled to make rubber acceptable for the purposes of the instant invention. The material of the envelope may be formed of the same or of different plastic.

The slider '14 is preferably formed of metal for rigidity and convenience of construction and may be formed by a stamping process. Other non-resilient materials may be suitable in some circumstances such as plastics or rubber of suitable strength.

The slider 14 has sides 39' and 31 which extend downwardly over the edges of the strips and have opposed inwardly facing closing surfaces 32 and 33. The sides and surfaces 32 and 33 taper inwardly from the feed end '14:! to the closing end 14b to provide a closing pressure to the outer surfaces 27 and 28 of the strips when the slider is moved in the closing direction (to the left in FIGURE 1). The sides are rigidly mounted on a back 34 and the sides and back may be formed of an integral sheet of material with the sides turned downwardly substantially at right angles to the back 34.

In each of the sides 33 and 31 adjacent the closing end 1412 of the slider is formed a vertical locking rib 35 and 36 respectively. The ribs are conveniently formed by providing a vertical indentation into the sides 30 and 31. The ribs and 36 provide a rounded projection which rides along the closure strips pressing them firmly together. The closure strips are engaged by the ribs 35 and 36 which press the resilient material inwardly. The strips of course are brought together sufliciently firmly by the tapered sides 3% and 31 to cause interlocking of the strips but the pressure of the ribs insures that the strips will mate in interlocking engagement. This additional pressure does not interfere with the locking function of the sides of the slider and permits wider manufacturing tolerances both in the slider and in the strips. The ribs also provide some additional strength for the sides 30- and 31.

At the feed end 14a of the slider 14 is a separator finger 3'7 which is integral with the back 34 and projects downwardly therefrom between the strips to separate them when the slider is moved in the opening direction (to the right as shown in FIGURE 1).

At the lower end of the finger 37 is a tapered plate or tab 3-9 which projects toward the closing end or" the slider. The tab projects beneath the marginal portions 16' and 18 of the closure strips and rides beneath the surface of the projection 29 on the strip 12 holding the slider in place over the edges of the strips. The tab 3? may also aid the finger 37 in separating the closure strips when moved in the opening direction.

The finger 37 is formed with a groove 3% Which strengthens the finger preventing bending or distortion when it is unduly forced against the strips. The groove '38 extends into the back 34 and down into the tab 39. This aids in holding the finger rigid relative to the slider and strengthens the attachment between the finger 37 and the tab .39.

As illustrated in FIGURE 5, the inner side of the finger is formed with a ridge facing the closing end of the slider. The slider and the separator finger 37 are preferably formed of sheet metal and in stamping the metal and providing the groove 68 the ridge 4t) is automatically formed. This ridge also strengthens the finger and the sloping material at the sides of the ridge 4t) provides a convenient surface for engaging and separating strips 12 and 13 when the slider is moved in an opening direction.

In operation, the slider 14 is moved in a closing direction (to the left as shown in FIGURE 1) and the closure strips 12 and 13 are forced together to interlock the strips by the surfaces 32 and 33, and the vertical ribs 35 and 36 insure interlocking engagement of the strips. When the slider 14- is moved in opening direction (to the right as shown in FIGURE 1) the finger 37 separates the strips and is strengthened against bending by the groove 38 formed therein.

Thus it will be seen that I have provided an improved closure and an improved slider therefore which meets the objectives and advantages hereinabove set forth. The structure is well adapted for mass production manufacturing methods and is of increased strength and functions in an improved manner for opening and closing closure strips.

The drawings and specification present a detailed disclosure of the preferred embodiments of the invention, and it is to be understood that the invention is not limited to the specific forms disclosed, but covers all modifications, changes and alternative constructions and methods falling within the scope of the principles taught by the invention.

1 claim as my invention:

1. A flexible closure comprising in combination,

a pair of flexible closure strips each having web portions and marginal portions at the upper edge thereof, the marginal portion of one strip being above its web portion and substantially parallel thereto being offset inwardly to provide a downwardly facing shoulder, the marginal portion of the other strip being alongside its web portion and being attached by its upper edge to the upper edge of its marginal portion by an integral hinge portion, interlocking facing rib and groove elements extending along the inner surfaces of the marginal portions,

a slider straddling the upper edge of the strips and movable in one direction for joining the strips and in the other direction for separating the strips,

said slider having a back above the strips and having side integral therewith extending downwardly from the back and tapering together toward a closing end of the slider for forcing the strips together and diverging toward an opening end of the slider,

the lower edges of the sides being smooth and straight,

said slider further having a substantially straight separator finger bent downwardly from the back and integral therewith being intermediate the sides and being substantially the length of the sides and projecting between the strips for separating them when moved in an opening direction with the finger at the opening end of said slider,

said finger shaped to have a ridge facing the closing end of the slider and to have a V-shaped groove facing the opening end of the slider with the finger being cantilever mounted,

a fiat holding portion integral with the lower end of the finger and bent rearwardly toward the closing end of the slider being substantially at the level of said straight edges of the sides of the slider and being substantially shorter than the length of the slider,

the edges of said holding portion extending substantially parallel to the sides of the slider to provide channels for the strips between the holding portion and each of the sides of uniform width along the length,

and vertical indentations on each of the sides at the closing end thereof extending substantially the full length of the sides but terminating short of the lower edge thereof so that the straight smooth edge is not interrupted,

the upper surface of said holding portion riding beneath said shoulder of the marginal portion retaining the slider on the strips and holding it parallel to the strips.

2. A flexible closure comprising in combination,

a pair of flexible closure strips each having web poltions and marginal portions at the upper edge thereof,

the marginal portion of one strip being above its -web portion and substantially parallel thereto, the marginal portion of the other strip being alongside its web portion and being attached by its upper edge to the upper edge of its marginal portion by an integral hinge portion,

one of said marginal portions providing a downwardly facing shoulder located between the strips,

interlocking facing rib and groove elements extending along the inner surfaces of the marginal portions,

a slider straddling the upper edge of the strips and movable in one direction for joining the strips and in the other direction for separating the strips,

said slider having a back above the strips and having sides integral therewith extending downwardly from the back and tapering together toward a closing end of the slider for forcing the strips together and diverging toward an opening end of the slider,

the lower edges of the sides being smooth and straight,

said slider further having a substantially straight separator finger bent downwardly from the back and integral therewith being intermediate the sides and being substantially the length of the sides and projecting between the strips forseparating them when moved in an opening direction with the finger at the opening end of said slider,

said finger shaped to have a ridge facing the closing end of the slider and to have a V-shaped groove facing the opening end of the slider with the finger being cantilever mounted,

a fiat holding portion integral with the lower end of the finger and bent rearwardly toward the closing end of the slider being substantially at the level of said straight edges of the sides of the slider and 6 being substantially shorter than the length of the slider,

the edges of said holding portion extending substantially parallel to the sides of the slider to provide channels for the strips between the holding portion and each of the sides of uniform width along the length, and vertical indentations on each of the sides at the closing end thereof extending substantially the full length of the sides but terminating short of the lower edge thereof so that the straight smooth edge is not interrupted,

the upper surface of said holding portion riding beneath said shoulder of the marginal portion retaining the slider on the strips and holding it parallel to the strips.

References Cited in the file of this patent UNITED STATES PATENTS 2,035,675 Sipe Mar. 31, 1936 2,041,156 Sundback May 19, 1936 2,160,819 Behrens June 6, 1939 2,171,335 Gross Aug. 29, 1939 2,364,100 Savitzky Dec. 5, 1944 2,671,257 Shur Mar. 9, 1954 2,677,162 Foltis May 4, 1954 2,764,793 Sander Oct. 2, 1956 2,777,181 Morner Jan. 15, 1957 3,054,434 Ausnit Sept. 18, 1962 FOREIGN PATENTS 564,633 Belgium Feb. 28, 1958 

1. A FLEXIBLE CLOSURE COMPRISING IN COMBINATION, A PAIR OF FLEXIBLE CLOSURE STRIPS EACH HAVING WEB PORTIONS AND MARGINAL PORTIONS AT THE UPPER EDGE THEREOF, THE MARGINAL PORTION OF ONE STRIP BEING ABOVE ITS WEB PORTION AND SUBSTANTIALLY PARALLEL THERETO BEING OFFSET INWARDLY TO PROVIDE A DOWNWARDLY FACING SHOULDER, THE MARGINAL PORTION OF THE OTHER STRIP BEING ALONGSIDE ITS WEB PORTION AND BEING ATTACHED BY ITS UPPER EDGE TO THE UPPER EDGE OF ITS MARGINAL PORTION BY AN INTEGRAL HINGE PORTION, INTERLOCKING FACING RIB AND GROOVE ELEMENTS EXTENDING ALONG THE INNER SURFACES OF THE MARGINAL PORTIONS, A SLIDER STRADDLING THE UPPER EDGE OF THE STRIPS AND MOVABLE IN ONE DIRECTION FOR JOINING THE STRIPS AND IN THE OTHER DIRECTION FOR SEPARATING THE STRIPS, SAID SLIDER HAVING A BACK ABOVE THE STRIPS AND HAVING SIDE INTEGRAL THEREWITH EXTENDING DOWNWARDLY FROM THE BACK AND TAPERING TOGETHER TOWARD A CLOSING END OF THE SLIDER FOR FORCING THE STRIPS TOGETHER AND DIVERGING TOWARD AN OPENING END OF THE SLIDER, THE LOWER EDGES OF THE SIDES BEING SMOOTH AND STRAIGHT, SAID SLIDER FURTHER HAVING A SUBSTANTIALLY STRAIGHT SEPARATOR FINGER BENT DOWNWARDLY FROM THE BACK AND INTEGRAL THEREWITH BEING INTERMEDIATE THE SIDES AND BEING SUBSTANTIALLY THE LENGTH OF THE SIDES AND PROJECTING BETWEEN THE STRIPS FOR SEPARATING THEM WHEN MOVED IN AN OPENING DIRECTION WITH THE FINGER AT THE OPENING END OF SAID SLIDER, SAID FINGER SHAPED TO HAVE A RIDGE FACING THE CLOSING END OF THE SLIDER AND TO HAVE A V-SHAPED GROOVE FACING THE OPENING END OF THE SLIDER WITH THE FINGER BEING CANTILEVER MOUNTED, A FLAT HOLDING PORTION INTEGRAL WITH THE LOWER END OF THE FINGER AND BENT REARWARDLY TOWARD THE CLOSING END OF THE SLIDER BEING SUBSTANTIALLY AT THE LEVEL OF SAID STRAIGHT EDGES OF THE SIDES OF THE SLIDER AND BEING SUBSTANTIALLY SHORTER THAN THE LENGTH OF THE SLIDER, THE EDGES OF SAID HOLDING PORTION EXTENDING SUBSTANTIALLY PARALLEL TO THE SIDES OF THE SLIDER TO PROVIDE CHANNELS FOR THE STRIPS BETWEEN THE HOLDING PORTION AND EACH OF THE SIDES OF UNIFORM WIDTH ALONG THE LENGTH, AND VERTICAL INDENTATIONS ON EACH OF THE SIDES AT THE CLOSING END THEREOF EXTENDING SUBSTANTIALLY THE FULL LENGTH OF THE SIDES BUT TERMINATING SHORT OF THE LOWER EDGE THEREOF SO THAT THE STRAIGHT SMOOTH EDGE IS NOT INTERRUPTED, THE UPPER SURFACE OF SAID HOLDING PORTION RIDING BENEATH SAID SHOULDER OF THE MARGINAL PORTION RETAINING THE SLIDER ON THE STRIPS AND HOLDING IT PARALLEL TO THE STRIPS. 